Plansifter.



A. sc'H'AR.

PLANSIFTER.

APPLICATION FILED MAY 3. I918.

Patented July 2, 1918.

TWE.

ALFRED SCHAR, 0F FLAWIL, SWITfiERLANJD.

rnansrrrnn.

Specification of Letters Patent.

Patented July 8, 1218.,

Application filed May 3, 1918. Serial No. 232,390.

lowing to be a clear, full, and exact descrip .tion of the invention, such Wlll enable others skilled in the art to which it appertain's to make and use the same, reference being had to the accompanying drawing, and to letters-or figures of reference marked thereon, which forms a part of this specification.

. This invention has reference to improvements in plansifters and comprises two sieve boxes arranged diametrically with regard to a vertical driving shaft which actuates said boxes by means of a double crank. Said sieve boxes arecoupled crosswise by means of two levers arranged syi'nmetrically with regard to the driving shaft, so that the sieve boxes are moved upon their actuation simultaneously toward and away from each other.

This invention will now be more particularly described with reference to the accompanying drawing illustrating by way of example one way of carrying the invention into efiect.

In this drawing:

Figure 1 is a front elevation and Fig. 2 a plan view of the plansifter.

Each of the two sieve boxes 15 and 15" is supported by means of two gudgeons 6, 6 and 6 6 respectively. The two boxes 15 15 are connected to two levers. One of said levers consists of a two arm lever 8 adapted to rotate about a stationary gudgeon 16, the arms of said lever 8 having the same length. The lever 8 supports at its two ends, 71. e. at two points lying at the same dis? tance from the pivot 16 two journals 7 a and 7 respectively. In the journal 7 is mounted one end of a rod 1; the other end of the latter supports the sieve box 15 by means of the gudgeon 6 fixed at 5 to said box 15. In the other journal 7 referred to is mounted one end of a rod 4 supporting at its other end the sieve box 15 by means of the gudgeon 6. The second lever consists of a two arm lever 18, the arms of which have the same length; the lever 18 is the same size as the lever 8. Lever 18 is pivoted on a stationary gudgeon 16 and it supports at its ends two journals 7" and 7 respectively. In journal '7 is mounted one end of a rod 2 said rod supporting at the other end the sieve box 15 by means of the gudgeon 6 which is fixed at 5 to said box 15 In journal 7 c is mounted one end of a rod 3 said rod supporting at itsother end the sieve box 1:5 by means of the gudgeon 6". The rods 1 and 2 are of equal length and the rods 3 and 4 are ofequal length.

The stationary pivots 16 and 16 are arranged with regard to a vertical driving shaft 17 supported at its upper end in a bearing 9, and diametrically opposite each other. Beneath the bearing 9 is fixed to the driving shaft 17 a pulley 19 whichis for actuating said shaft, while above said bearing 9 is fixed to the shaft 17 a double crank 10. The two crank pins 11 and 12 describe the same crank circle, the shaft 17 constituting the center of said circle. An arm 13 connected to the sieve box 15" engages with the crank pin 11, while an arm 1 1 connected to the sieve box 15 engages with the crank pin 12. The arms 13 and 1% have the same length. The crank pins 11 and 12 are arranged diametrically opposite each other.

Let it now be assumed that the shaft 17 is rotated by the pulley 19 in a clockwise direction and that the parts take up at first the position shown in Fig. 2 in full lines. The crank pins 11 and 12 are then caused to describe the same circle and the two sieve boxes 15 and 15" are moved toward each other, 2'. 6. they are moved into the position illustrated in Fig, 2 in point and dash lines. Thereby, the arm 13 draws the sieve box 15 (in Fig. 2) downward and the arm 14.- draws the sieve box 15 (in Fig. 2) upward. In consequence of this, the journals 7 and 7 supported by the lever 8 are caused to move in a circle having the pivot 16 as center, while the journals 7 and 7 supported by the lever 18 are caused to move in a circle having the pivot 16 as center. The rods 1, 2, 3 and a exert thereby a pulling action upon the sieve boxes 15 and 15 respectively, so that they are moved toward each other, the rod 1 pulling the box 15 toward the driving shaft, while the journal 7 on the other .end of the lever 8, caused to move in a clockwise direction, draws the box 15 toward the driving shaft 17 Similarly the rod 2 draws the sieve box 15 toward the driving shaft and the journal 7 caused to move in an anti-clockwise direction draws the box 15 toward the driving shaft 17.

This manner of operations is a consequence of the crosswise coupling of the two sieve boxes 15 and 15 by means of two levers which are arranged symmetrically with regard to the central driving shaft 17 and are adapted to be moved with regard to the latter in the same manner as the two blades of scissors. Upon an opening movement of those parts of the levers 8 and 18 which c0- operate with the rods 3 and 1, the parts of the levers 8 and 18 cooperating with the rods 1 and 2 are moved toward each other and vice'versa.

Itis evident that upon a rotation of the driving shaft 17 the sieve boxes 15 and 15 are moved along the curves illustrated in Fig. 2 in the direction of the arrows shown. Upon an actuation of the plansifter, the sieve boxes are thus moved simultaneously toward and away from each other. Since the arrangement of the levers is symmetrical, and as no heavy machine members gyrate in either of the two sieve boxes, no balancing weights or special gyrating masses have to be provided in a plansifter designed according to this invention. The hereinbefore describing plansifter works in a very quiet manner, all shocks being eliminated and. its design is of a very light character, so that it can be erected in any building, the

'latter never bein dama ed b shakin 's produced by the plansifter.

What I claim now as my invention is: 1. In a plansifter, in combination, a driving shaft, a double crank fixed to said shaft, two sieve boxes arranged diametrically with regard to said driving shaft, means connecting the sieve boxes, to said crank, and two levers arranged symmetrically with regard to the driving shaft and coupling the two boxes crosswise, so that the latter are moved upon an actuation of the plansifter simultaneously toward and away from each other.

2. In a plansifter, in combination, a driving shaft, a double crank fixed to said shaft, two sieve boxes arranged diametrically with regard to said driving shaft, means connecting the sieve boxes to said double crank, and two levers arranged symmetrically with regard to said driving shaft and coupling the two boxes crosswise, each of said levers comprising two arms pivoted at a point outside the driving shaft, the two points being arranged synnnetrically with regard to the driving shaft.

3. In a plansifter, in combination, a driving shaft, a double crank fixed to said shaft, two sieve boxes arranged diametrically with regard to said driving shaft, means connecting the sieve boxes to said double crank, two levers arranged symmetrically with regard to said driving shaft, a pivot for each of said levers, the two pivots lying outside the driving shaft and arranged symmetrically with regard to said shaft and each lever comprising two arms, and a rod connected to an end of each of said levers and one rod of each lever being pivotally connected to one sieve box and the other rod fixed to the same lever being pivotally onnected to the second sieve box at a point lying with regard to the driving shaft diametrically opposite the point at which said first mentioned rod is connected to the first sieve box.

In testimony that I claim the foregoing as my invention, I have signed my name.

ALFRED soHAR.

oggles of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

